High Bridge

High Bridge was built as part of the original Croton Aqueduct project
to bring water from the Westchester River to Manhattan.
The bridge also incorporates a pedestrian walkway between the Bronx and
Manhattan at 174th street. The bridge went into active service in 1848, making it the
oldest extant bridge in New York City.

The bridge design was overseen by Aqueduct engineer John B.
Jervis and James Renwick, Jr., who went on to oversee the construction of
Manhattan's St. Patrick's Cathedral. The original design incorporated 15
circular masonry arches with a maximum length of 80 feet, giving the bridge
a 114-foot clearance above mean high water.

The old Croton Aqueduct was made obsolete by a new series of tunnels and
water flow was shut off on February 3, 1917 as part of security measures on
the day the U.S. entered World War I. The Army Corps of Engineers wanted
to demolish the bridge as an obstruction to river traffic, but a
coalition of citizens groups pursuaded the Corps to replace five masonry
arches with a steel arch in 1927.

There is some question as to the reason for and date of the bridge's closing.
A posting on WiredNY...

I don't know where the rumor that the High Bridge was closed in the early 1970s
after a fatal rock throwing incident, but it is pure nonsense, the result of
lazy newspaper reporters who don't know how to, or don't care to, research.
I have been attempting to ascertain exactly when it was closed, and have thus
far been unable to, but it was definitely between 1958 and 1968, and most
likely between 1958 and 1962.

I have conducted an exhaustive, extensive study
of the New York Times Archives. On April 20, 1958, four youths threw bricks,
sticks, and rocks onto the Circle Line as it passed under the High Bridge.
Four people were injured, none seriously. When the New York Press ran a story
on the High Bridge, someone wrote the next week, stating that he had moved to
the Highbridge section of the Bronx in 1962, and the bridg had been closed
even then. A New York Times reporter who followed the trail of the Croton
Aqueduct in 1968 stated that the High Bridge was closed.

3/12/2005 04:24 PM
View from the South

3/12/2005 04:30 PM
View from the Southwest

3/12/2005 04:30 PM
The arch section viewed from the south

3/15/2005 09:56 AM
Highbridge Park on the East side of the bridge

3/15/2005 09:57 AM
View from the East

3/15/2005 09:59 AM
Menacing gate blocking pedestrians from the East

3/15/2005 10:00 AM
The bridge viewed from a hole in the East gate

3/15/2005 10:06 AM
Stair structure leading down from Highbridge Park

3/15/2005 10:14 AM
Stairway down from Highbridge Park

3/15/2005 10:06 AM
View from the Southeast

3/15/2005 10:08 AM
Arches on the East side

3/15/2005 10:09 AM
Arches on the East side

3/15/2005 10:10 AM
Detail of brickwork

The Western approach to the bridge is considerably more forbidding.
The old water tower has been lovingly cared for and the upper level
of Highbridge Park (which includes a Robert Moses-era pool and recreation area)
is still actively used. However, the stairway down to the bridge has not been
maintained since the bridge was closed.